Roll your clothes instead of folding them to prevent creases and to conserve space

Minimize creases by putting the same type of garments on top of each other and folding them together. The outermost garments won't
wrinkle as much

For extremely delicate items wrap tissue paper around them before folding to prevent creases

Airlines differ slightly on carry-on size and baggage weight requirements. Be sure to check with your specific airline - especially if
your traveling on a budgetairline

If your bag gets randomly selected for screening and it doesn't have a TSA-approved lock, airport authorities have the right to break
the lock. TSA-approved locks have a special access port for TSA keys

If you had a hard time closing your luggage, so will airport inspectors but they won't be as fussy about random articles falling off
and such. Overpacking is a bad idea